External Counter Pulsation (ECP) is a safe and effective, non-invasive treatment to assist circulation, particularly in the treatment of ischemic heart disease. “Counter Pulsation” improves heart function by increasing blood flow through the coronary vessels using a series of cuffs, fastened about the legs and buttocks, which contain inflatable bladders.
“External” means that the treatment is applied to the exterior of the of the patient's body. Surgery is not required.
The treatment system compresses the legs from the calves through the thighs, and the buttocks, sequentially by inflating sets of bladders encased in flexible, fabric cuffs during the resting phase of the heart cycle (diastole). This results in the movement of blood from the legs toward the heart through both the arterial and the venous systems.
Each wave of pressure is electronically timed to a heart beat, so that the increased blood flow is delivered to the heart during the time period the heart is relaxing (diastole). Before the heart begins to contract again (systole), the pressure is rapidly released. This lowers resistance in the blood vessels of the legs so that blood may be pumped more easily from the heart, decreasing the amount of work required of the heart muscle. This is evidenced by a reduction in the patient's systolic pressure.
The aortic valve is the heart valve through which blood leaves the left ventricle, the main pumping chamber of the heart, and which prevents back flow into the left ventricle. The coronary arteries open off the aorta, above the aortic valve, and the pressure applied to the lower extremities drives extra blood into the aorta and through the coronary arteries, expanding the heart's networks of tiny auxiliary blood vessels. This is evidenced by the increase in the patient's diastolic pressure. The volume of blood flowing to the heart muscle is thus increased. Blood forced up the veins enters the right chambers of the heart. This is called “pre-loading” of the heart.
The typical ECP treatment regimen for chronic angina patients is 35 hours of treatment, usually one hour per day, five days per week for seven weeks. While not as desirable as the above-regimen, a 2-hour per day regimen can also be utilized, which reduces the time to completion to 3½ weeks. In the treatment of heart attacks, ECP can be administered for up to four hours, with a 10 minute rest period after each hour of treatment. Pressure is typically applied to produce a peak diastolic pressure to peak systolic pressure ratio (D/S Ratio) of 1.5:1 to 2:1 or higher in the treatment of chronic angina and heart attacks. The duration of treatment and rest intervals depend on the patient's condition, the degree of augmentation of diastolic pressure to systolic pressure obtained, patient tolerance and the like indications.
Congestive heart failure (CHF) affects an estimated two-and-one-half million people in the United States and causes approximately 400,000 deaths per year, a number almost equal to the deaths from all types of cancer combined. Other than implantable defibrillators and dual chamber, cardiac “resynchronization” pacemakers, which are extremely expensive (implantation of such a device in the U.S. currently costs $50,000 or more), require surgery and have shown only a reduction in mortality of about 50% from the American Heart Association's 18.8% annual mortality from CHF in the United States, there is presently no truly effective therapy for CHF.
It has now been found that ECP can be advantageously utilized to treat patients suffering from congestive heart failure and left ventricular dysfunction. Such patients frequently exhibit a left ventricular ejection fraction of 40 percent or less by volume (about 55 percent is normal), because the diseased heart is not able to pump with sufficient force to efficiently eject blood from the main pumping ventricle of the heart.
Currently practiced ECP methods, such as used in the treatment of chronic angina and heart attacks (i.e. at D/S Ratio of 1.5:1 to 2:1 or higher), however, can cause excessive pre-loading of the heart, and the heart cannot pump out or “eject” a sufficient amount of blood. This causes blood to “pool” in the blood vessels of the lungs, abdomen and extremities, as well as fluid to build-up in the lungs, calves, ankles and feet. The heart muscle necessarily works harder and thickens, which further reduces its pumping efficiency. As a result, more fluid builds up in the lungs, making it difficult for the patient to breathe. A recurrence or worsening of heart failure or even death can result. The present method, however, avoids such undesirable consequences and leads to a substantial long-term reduction in mortality and an improvement in the condition and quality of life of the patient.